It is well known that polymers, like other organically based waste materials, can generally be combusted to produce carbon dioxide, water and other products along with useable energy. Another oxidation process which can be utilized is wet air oxidation wherein the feed and oxidizing agent are pressurized to reaction conditions of from about 1500 to 2500 psig, heated to operating temperature and fed to a reactor for residence times of 0.5 to 1 hour. Catalytic oxidation processes can also be used to convert polymers to carbon dioxide, water and other products depending on the composition of the polymer. All of the known reaction techniques for recycling polymers, however, are generally directed toward achieving or nearly achieving complete oxidation of the polymer in order to recover the maximum amount of thermal energy. Accordingly, none of the known methods for oxidizing polymers has been successfully utilized for achieving selective oxidation to recover high yields of monomers and oligomers thereof which can be used to repolymerize the pure polymer.
The recovery of monomers from polymeric waste material is highly desirable because other means of recycling polymers such as melting thermoplastics and reshaping them into usable articles has only limited applications owing to the tendency of such polymeric materials to undergo progressive contamination and degradation leading to lower quality materials which are unsuitable for many applications.